Orthopedic implant devices, such as intramedullary nails, plates, rods, screws, Kirschner wires (“K-wires”), and screw and washer assemblies are often used to repair or reconstruct bones and joints affected by trauma, degeneration, deformity, fractures, and disease, such as Charcot arthropathy caused by diabetes in some patients, Hallux Valgus deformities, failed Keller Bunionectomies, Rheumatoid Arthritis, injuries, and severe deformities.
Moreover, infections and wound complications are a major concern in the aforementioned procedures. Wound closure is technically demanding for the surgeon, and devices that add surface prominence, such as plates or exposed screws, add to the difficulty by requiring greater tissue tension during incision reapproximation. This increases the risk of postoperative wound infections and dehiscence that may ultimately result in limb amputation.
Various implants have been utilized for surgical treatment of these bones and joints, including bone screws. Implants have also been utilized to treat severe deformities in the metatarsal and phalangeal bones, including multiple screws and plates. These multiple screws and plate implants have been commonly used in a first metatarsal-phalangeal fusion procedure to fuse the first metatarsal to the first phalangeal bone in hallux valgus deformities, failed Keller bunionectomies, rheumatoid arthritis, and other types of severe deformities in the metatarsal and phalange bones. While these devices allow fixation and promote fusion, they do not deliver restoration of the arch in a Charcot foot, they are not effective in metatarsal-phalangeal (MTP) fusion procedures, nor do they deliver uniform compression for various predetermined angles of compression.
Particularly, screw implants in MTP procedures are ineffective in delivering sufficient compression to the bones in the foot, preventing screw head break out, or delivering effective bending resistance. Moreover, hard to control dorsiflexion and valgus angles as well as skin irritation from proximity to the skin prevents these screw implants from being readily utilized for surgical treatment. Yet further, plate implants used with bone screws too have the same drawbacks as fixed varus and valgus angles, lack of direct compression across the MTP joint, and skin irritations from proximity to the skin reduce the effectiveness of these implants. Yet further, some screw implants are not available to be readily interchangeable from a fixed angle compression to a variable angle compression while utilizing a common bone anchor and minimizing the members required by a surgeon.
Still further, use of K-wires, screws, screw and washer assemblies, and plates for the reduction and internal fixation of arthrodesis, osteotomy, intra-articular and extra-articular fractures, and non-unions of bones and joints of the hand, foot, arm, leg and various other body parts are ineffective in delivering the strength necessary to maintain sufficient reduction and/or fixation of the fractured bone, maximizing cortical bone contact, retaining bones in most anatomically correct position, preventing screw head break out, minimizing the size of the incision(s) necessary to install the hardware, minimizing soft tissue and tendon disruption and/or displacement, stabilizing fixation of the fracture, easing mobility for the patient, and eliminating hardware profiles.
There is therefore a need for an intramedullary fixation assembly and method of use that overcomes some or all of the previously delineated drawbacks of prior fixation assemblies.